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AN-SOF Implements James R. Wait Theory for Ground Losses of LF/MF Radio Masts

AN-SOF has incorporated an innovative method based on the James R. Wait theory to accurately compute the ground losses of LF/MF radio masts. The correct calculation of power lost in the ground is crucial for determining the radiation efficiency of monopole antennas. To minimize energy losses, radial wire ground screens are typically installed.

To illustrate the efficacy of this implementation, a simulation has been carried out on an antenna tower 1/4 wavelength in height, placed over an average soil with a conductivity of 0.005 S/m and a dielectric constant of 13. The simulation incorporated 60 buried radials and calculated the E-field at 3 MHz as a function of distance for an antenna input power of 1 kW.

To activate this calculation in AN-SOF for LF and MF band frequencies, users need to select the Sommerfeld-Wait/Asymptotic or Radial wire ground screen options as the real ground plane in the Setup > Environment panel. Here is an article detailing the validation of this model: Enhanced Methodology for Monopoles Above Radial Wire Ground Screens.

Monopole antenna model with ground screen showing E-field variation as distance changes.

Who was James R. Wait?

James R. Wait was a Canadian engineer known for his academic qualifications and prolific contributions to electromagnetic propagation engineering. He was elected as a member of the National Academy of Engineering in 1977 and authored numerous papers and books. Born in Ottawa in 1924, Wait received his BS and MS in engineering physics and his PhD in electrical engineering from the University of Toronto. He held various research positions worldwide and became a professor at the University of Arizona. Those interested in learning more about Wait’s life may refer to the article “James R. Wait—Remarkable Scientist” by Ernest K. Smith, IEEE Transactions on Antennas and Propagation, Vol. 48, No. 9, pages 1278-1286, September 2000″.

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